The terms “tall grass” and “tall grasses” as used herein refer to switchgrass (Panicum viratum), miscanthus (particularly Miscanthus x giganteus), big bluestem (Andropogon gerardii), Indian grass (Sorgastrum nutans), reed canary grass (Phalaris arundinacea), and other tall perennial grasses harvested as biomass feedstocks for ethanol production and biorefining.
Tall grass biomass is expected to become a core element of our nation's strategy to replace imported oil and natural gas with renewable resources.
Currently, switchgrass is harvested in large rectangular bales (3×4×8 feet) weighing about 1,100 pounds (11.5 lb/ft3) at about 10 percent moisture (Austin, 2009). For example, a New Holland BB9080 large square baler intended for forage and straw crops reportedly produced switchgrass bales at an average bale density of 181.1 kg/m3 (11.3 lb/ft3) at 80% of the baler's plunger load setting; this baler was said to have the ability to produce switchgrass bales that approach 200 kg/m3 (12.5 lb/ft3) (Kemmerer and Liu, 2010).
The present inventors have reported their progress to develop better methods to collect and transport woody biomass (Dooley 2006; Lanning 2007; Dooley 2008; Dooley 2009). Our continuing goal is to engineer more efficient recovery and highway transport of plant biomass materials to second-generation bioenergy and biofuel plants.